In general, hairs are covered with sebum or the like secreted by themselves. Shampooing with detergents, soaps or the like and permanent waving cause the sebum to be removed more than the necessary. Due to a loss of smoothness, the shampooed or permed hair is dry, loose and hard in feel and difficult to comb, tending to split. To eliminate such inconvenience resulting from removal of sebum, a variety of hair care products have been developed as hair conditioners. Known hair care products typically contain as the active ingredient a quaternary ammonium salt, for example, a di-long chain, di-short chain alkyl ammonium salt such as dialkyl dimethyl ammonium chloride or a mono-long chain alkyl, tri-short chain alkyl ammonium salt such as alkyl trimethyl ammonium chloride.
However, these quaternary ammonium salts are not only stimulative to the hair and scalp, but also tend to leave the hair upon rinsing because they have a weak force of adsorption to the hair as a result of the steric hindrance that the charged nitrogen atom playing the role of an adsorption center is surrounded by long and short chain alkyl or alkenyl groups. Hair care products containing such a quaternary ammonium salt as the active ingredient need further improvements in imparting softness and smoothness to the shampooed hair because the active ingredient is insufficiently adsorbed to the hair. There is a need for the development of a hair care product containing an active ingredient which is sufficiently adsorbed to the hair to eliminate any inconvenience as experienced after shampooing or permanent waving.